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M20 x 125mm 304 Stainless Steel Hex Cap Screw

Expert Overview

This M20 x 125mm Hex Head Cap Screw, crafted from premium 304 Stainless Steel, offers superior corrosion resistance and high tensile strength. Engineered for reliability in demanding environments.

StandardASTM A106
Material304 Stainless Steel
FinishZinc Plated
GradeN/A
SizeM20
Length125mm
Head Width34mm

Detailed Engineering Specifications

Built to exacting engineering tolerances, this M20 x 125mm hex head cap screw features a nominal diameter of 20mm and a length of 125mm, with a precisely machined head width of 34mm. Constructed from 304 stainless steel, it provides exceptional resistance to corrosion, oxidation, and a wide range of chemicals, making it ideal for applications exposed to harsh environments. Its inherent strength and durability ensure secure and long-lasting connections in structural, marine, food processing, and chemical industries. The hex drive allows for high torque application, ensuring a robust and reliable joint.

🧊 Download 3D CAD Model (.STEP)

Verified Global OEM Partners

This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.

BossardEst. 1831
Switzerland🇨🇭
"Global leader in fastening technology."
Market Rank
🏆 Top 3 Global Fastener Network
Industry Approvals
🚀 Aerospace & Tesla Approved
Warranty & Support
🛡️ Lifetime Traceability
Green Manufacturing
🌱 Carbon Neutral by 2030
Certified:ISO 9001, RoHS, REACH
Würth GroupEst. 1945
Germany🇩🇪
"Premium assembly and fastening materials."
Market Rank
🏆 #1 Global Assembly Supplier
Industry Approvals
🚀 VW & BMW OEM
Warranty & Support
🛡️ 5-Year Industrial Warranty
Green Manufacturing
🌱 100% Recyclable Packaging
Certified:ISO 9001, DIN EN
Brighton-BestEst. 1925
USA🇺🇸
"Master distributor of industrial fasteners."
Market Rank
🏆 Largest Distributor in NA
Industry Approvals
🚀 Boeing Approved
Warranty & Support
🛡️ Global Replacement Guarantee
Green Manufacturing
🌱 Green Steel Initiative
Certified:ISO 9001, A2LA

Certifications & Compliance

RoHS Compliant:Yes
REACH Compliant:Yes
Material Traceability:Available on Request
DFARS Compliant:Yes

Installation Procedure

1. Select the appropriate wrench or socket size for the 34mm hex head. 2. Ensure the mating threads are clean and free of debris. 3. Apply a consistent and appropriate torque to achieve the desired clamping force, avoiding overtightening.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardASTM A106

Mechanical Properties

Tensile Strength75,000 psi (515 MPa)
Yield Strength30,000 psi (205 MPa)
Elongation in 2 in.40% min
HardnessRockwell B95 max

Chemical Composition

Carbon (C)0.08% max
Chromium (Cr)18.0 - 20.0%
Nickel (Ni)8.0 - 10.5%
Manganese (Mn)2.00% max

Temperature & Environment Rating

Min Operating Temp
-320°F (-195°C)
Max Continuous Temp
1400°F (760°C)
Thermal Expansion
Typical for Material Class

Recommended Torque Values

Bolt SizeDry Torque (ft-lbs)Lubricated Torque (ft-lbs)
M20Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M20Varies by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedExcellent
Marine / SaltwaterGood
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Using an incorrect size wrench, leading to cam-out and fastener damage.Always use a wrench or socket that precisely fits the 34mm hex head to ensure proper engagement and prevent stripping.
Cross-threading the screw, which can damage both the screw and the mating component's threads.Carefully start the screw by hand to feel the threads engage smoothly before applying any significant force.

Common Applications

  • Structural Steel Connections
  • Marine and Offshore Equipment
  • Food Processing Machinery
  • Chemical Plant Infrastructure

⚠️ Engineering Warnings

  • Ensure proper torque is applied to prevent overstressing or under-securing the connection.
  • Verify compatibility of mating materials to avoid galvanic corrosion in specific environments.

Alternative Products to Consider

Premium Fastening & Joining equivalentHigher corrosion resistance (316 SS)
Economy Fastening & Joining optionLower cost for non-critical indoor applications

Frequently Asked Questions

Q: What is the Hex Head Cap Screw, 304 Stainless Steel made from?

A: This Hex Head Cap Screw, 304 Stainless Steel is manufactured from 304 Stainless Steel.

Q: What are the main applications?

A: Structural Steel Connections, Marine and Offshore Equipment, Food Processing Machinery, Chemical Plant Infrastructure.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 125mmAF34mm1/2"-13TIGHTEN →MECHANICAL PROPERTIESTensile Strength: 150,000 psiThread: 1/2"-13 UNCTorque Direction: Clockwise (CW)Head Marking: 6 radial lines (Grade 8)

Torque Specifications

⚡ UNIT CONVERTER

Conversion factor: 1 ft-lb ≈ 1.356 Nm

Verified Compatibility

StatusMating ComponentStandardTorque SpecEngineering Notes
No verified compatibility data found for this component.